Some hardware will ignore bit TRCPDCR.PU which is used to signal to hardware that power should not be removed from the trace unit. Let's mitigate against this by saving and restoring the trace unit state when the CPU enters low power states. To provide a benefit to both self-hosted and external debuggers we save/restore the entire state which includes etmv4_config data and dynamic data such as inflight counter values, sequencer states, etc. Andrew Murray (5): coresight: etm4x: remove superfluous setting of os_unlock coresight: etm4x: use explicit barriers on enable/disable coresight: etm4x: use octal permissions for module_params coresight: etm4x: improve clarity of etm4_os_unlock comment coresight: etm4x: save/restore state across CPU low power states drivers/hwtracing/coresight/coresight-etm4x.c | 260 +++++++++++++++++- drivers/hwtracing/coresight/coresight-etm4x.h | 66 ++++- drivers/hwtracing/coresight/coresight.c | 2 +- include/linux/coresight.h | 7 + 4 files changed, 327 insertions(+), 8 deletions(-) -- 2.21.0 _______________________________________________ linux-arm-kernel mailing list linux-arm-kernel@xxxxxxxxxxxxxxxxxxx http://lists.infradead.org/mailman/listinfo/linux-arm-kernel